Power systems typically include redundant components to prevent power outages. FIG. 8 illustrates an example of using redundant components in a power system. An uninterruptible power supply (UPS) 810 and a UPS 820 supply power to a power distribution unit (PDU) 830, which may be connected to power supplies and electrical devices, i.e., the load, not shown. The UPS 810 and UPS 820 are redundant components and may equally share the load demand of the PDU 830. That is the PDU 830 may draw a substantially equal amount of current from the UPS 810 and the UPS 820 to meet the load demand on the PDU 830. If the UPS 810 fails, then the UPS 820 is available to meet the load demand of the PDU 830 on its own. However, the UPS 820 must be sufficiently provisioned, i.e., must have sufficient capacity, such that the UPS 820 can meet the load demand of the PDU 830 on its own. Furthermore, the UPS 820 may be sharing the load demand of another PDU 840 with another UPS (not shown), and if that UPS fails then the UPS 820 may have to support two loads on its own. Thus, the UPS 820 must be substantially over provisioned to prevent power outages.
Over provisioning components in a power system and using redundant components are fail-safe techniques, but these techniques dramatically increase operating and implementation costs. Typically, as the capacity of a UPS or other power system component increases, costs also increase. Furthermore, even if redundancy and over provisioning are used, the power system may still be susceptible to the “snow ball effect”. For example, if the UPS 810 fails then the UPS 820 must meet the load demand of the PDUs 830 and 840. At peek demand intervals, the combined demand of the PDUs 830 and 840 may exceed the capacity of the UPS 820. For example, the UPS 820 may have been designed to have a capacity to meet a lower peek demand, but the peek demand may have increased over time. If the UPS 820 fails, the resulting increased loading may cause other UPSs in the power system to fail, realizing the snow ball effect.